Articulated aquatic flipper



P 1964 J. R. HAMBLIN 3,146,470

' ARTICULATED AQUATIC FLIPPER Filed May 6, 1963 2 Sheets-Sheet 1 JESSER. HAMBL/N INVENTOR 14 TTOPNEKS P 1, 1954 .1. R. HAMBLIN 3,146,470

ARTICULATED AQUATIC FLIPPER Filed May 6, 1963 2 Sheets-Sheet 2 F JESSER. HAMBLM/ 6 7). IN V E N TOR A 7TORNEV$ United States Patent 3,146,470ARTiCULATED AQUATIC FLIPPER Jesse R. Harnblin, 512 McDonald Way,Bakersfield, Calif. Filed May 6, 1963, Ser. No. 278,263 3 Claims. (Cl.9-307) The present invention relates to an articulated aquatic flipperparticularly adapted for use as a propelling fin for swimmers.

Various types of flexible fin-like devices have been fabricated for useon the feet of swimmers as aids to propelling themselves through water.Such devices have primarily served to increase the total reactionsurfaces available to swimmers so as to permit a more efficientutilization of the swimmers energy. Such known devices have not beensuited for manual use, in that different stroking characteristics arerequired for leg and arm propulsion during swimming. Generally, rigidattachrnents, as well as flexible fins of limited rigidity, have beenfound to be unsuited for use as flippers for attachment to the arms andhands of swimmers.

Previously known devices for hand attachment have been of excessiveweight in relation to their utility, and have been unable to fold to areturn stroke position thereby to reduce the frictional drag incident totheir use. While certain of such devices have been of insufficientrigidity to permit full utilization of the swimmers energy, others of amore rigid nature have not provided suitable attachment means so thatexcessively high stress forces have been imposed on the wrists and handsof users.

Accordingly, it is an object of the present invention to provide alightweight aquatic flipper which affords an area of reaction surfacesuflicient for effective swimming.

Another object is to provide an articulated aquatic flipper whichautomatically opens to an extended swimming position during use and alsofolds to a closed return position during appropriate swimming strokes.

Another object is to provide an aquatic flipper as an aid to swimmerswhich permits releasable attachment to the hand and arm of a user.

A further object is to provide an aquatic flipper of minimum dimensionsthereby to minimize total weight while providing adequate surface areafor efficient utilization.

A still further object is to provide in an articulated aquatic flipperreinforcing structure to prevent the imposition of high stress forces onthe wrist of a wearer.

These, together with other objects, will become more fully apparent uponreference to the following description and accompanying drawings.

In the drawings:

FIG. 1 is a view in side elevation of a pair of articulated aquaticflippers embodying the principles of the present invention as worn by aperson swimming in a body of water.

FIG. 2 is a view, somewhat enlarged, in side elevation of one of theflippers shown in FIG. 1 in an extended swimming position.

FIG. 3 is similar to FIG. 2 but showing the flipper in a folded, returnstroke position.

FIG. 4 is a top plan view of the articulated flipper of FIG. 2.

FIG. 5 is a view in front elevation taken from a position indicated bythe line 5--5 in FIG. 2.

FIG. 6 is a view in vertical, transverse section taken on line 66 ofFIG. 4.

FIG. 7 is a view in vertical, transverse section taken on line 7-7 ofFIG. 4.

Referring more particularly to FIG. 1 of the drawings, a pair ofindividual, articulated, aquatic flippers 10 are 3,146,470 PatentedSept. 1, 1964 illustrated attached to the arms and hands of a. swimmerpropelling himself through a body of water. As can be seen more clearlyin FIGS. 2, 3 and 4, each of the flippers It) includes an elongatedsupport plate 11 having respective forward and trailing ends 12 and 13.The plate also provides a downwardly disposed contact surface 14 adaptedto rest upon the back of the hand of the wearer. The plate 11 isprovided with a rearward arcuate portion 15 affording a curved surfacepartially to embrace the wrist and forearm of the wearer, thereby totransmit stress forces directly to the forearm. Such a construction andarrangement relieves the Wrist of a major portion of the burden of suchstress forces during swimming. To facilitate transmittal of such stressforces and to enhance the longitudinal rigidity of the plate, aplurality of longitudinally extended, transversely spaced reinforcingribs 16 are individually secured to the upper surface of the plate, asby rivets 17. As can be seen in FIG. 4, the reinforcing ribs 16 arearranged in a forwardly divergent pattern so as to provide a suflicientwidth at the forward end to support a web, subsequently to be described,and which provides the necessary water reaction surface for the flipper.

A handle 20 is provided for manual grasping by the wearer and includesan attaching yoke 21 secured to the plate 11 as by the upset ends 22 ofthe yoke. If desired, the ends 22 may be rigidly secured to the plateafter the yoke has passed through suitable apertures provided therein. Acylindrical roller 23 is supported on the yoke and adapted to be graspedby the swimmer during use of the flipper.

A wrist band 25 permits releasable attachment of the flipper to the armof the wearer. The band includes opposite ends 26 and 27, as shown inFIG. 7, each of which is anchored to the plate, as by rivets 28. Abuckle 29 permits ready attachment of the flipper to an arm of thewearer.

A plurality of transversely spaced jointed rib members 35 are disposedin forwardly divergent relationship, as can be seen in FIG. 4. Each ofthe rib members is provided with forward and rearward elongated sections36 and 37, respectively, which are pivotally interconnected by a pivotpin 38. It can be seen that the forward ends 39 of the rib members aremore widely spaced than the rearward distal ends 40. Each of the ribmembers 35 is provided with an integral upwardly projected reinforcingfin 41, which can be not-ed in FIG. 5. A pair of laterally projectedflanges 42 extend from opposite sides of the fin 41 and afford lowerattachment surfaces 43.

Articulation of the rib members relative to the support plate 11 isprovided by individual pivot pins 50, each affording a substantiallytransverse pivotal axis for its respective jointed rib member. Anindividual stop pin 51 is rigidly carried by each of the elongatedreinforcing ribs 16 so as to limit the range of movement of the jointedrib members to an extended swimming position, shown in FIG. 2. For asimilar purpose, each of the jointed rib members is provided with a stoppin 52 disposed adjacent to its respective pivotal connection providedby the pin 38.

A web 60 of flexible material is secured to the attachment surface 43afforded by the laterally projecting flanges 42. A suitable Waterproofadhesive effects a satisfactory attachment of the web to the flanges.Alternatively, the web may be secured by rivets, and other suitablemechanical means of attachment will readily occur to those skilled inthe art. The web 60 is extended transversely between the furthermost ribmembers 35 which define the lateral limits of the flipper. The webthereby provides a lower surface 61 which serves as a reaction surfaceduring the swimming stroke and when extended to the position shown inFIG. 2.

An example of an ideal material particularly adapted for use as the web60 in the present invention is relatively thin, sheet rubber or otherlike, elastomeric material. The web material should be sufficientlyflexible readily to permit automatic folding of the flipper to theposition shown in FIG. 3 during a return stroke. In addition to thedesired flexibility, the web should also be sufliciently longitudinallyand laterally dimensionally stable so as to resist stretching whenproviding a reaction surface in an extended swimming position and whenbeing used in propelling the user through the water.

Examples of materials excellently suited for use in the flipper of thepresent invention in fabricating the support plate and jointed ribmembers are aluminum, magnesium, and synthetic resins impregnated withreinforcing fibers, such as that commercially available and sold underthe trademark Fiberglas. Such materials are relatively free fromoxidation in moist conditions, are of low density and are sufficientlylongitudinally rigid to withstand the force imposed during use of theflipper.

Operation The operation of the described embodiment of the subjectinvention is believed to be readily apparent and is briefly summarizedat this point. The flipper is readily attached to the arm and hand ofthe intended user by manually grasping the roller 23 of the handle 20and fastening of the belt 25 about the wrist. Consequently, the wearercan transmit a propelling force to the flipper through the attachingyoke 21 and the upset ends 22 engaging the plate 11.

During the power or swimming stroke, as illustrated by the position ofthe right arm of the wearer in FIG. 1, the flipper of the presentinvention is automatically extended to a swimming position, more clearlyshown in FIG. 2. Such automatic extension is insured by reason of therelative large reaction area afforded by the web 60 in relation to themass of the jointed rib members 35 and because of the flexibility of theweb and the pivotal connection of the rib members to the plate 11.

Following completion of the power, or swimming, stroke, the swimmer doesnot always raise his hand above the surface of the water to make areturn for the initiation of a subsequent power stroke. In the eventthat the wearer maintains his hand below the surface, as in the case ofuse during skin diving, or other swimming below the surface of thewater, the flipper automatically assumes a folded, return strokeposition, as illustrated in FIG. 3. Such automatic assumption of afolded position during the return is accommodated by the pivot pins 38and 50 and the flexibility of the web 66. Regardless of the point atwhich a successive power stroke is initiated, the flipper automaticallyreturns to an extended swim ming position upon initiation of the powerstroke.

Accordingly, the present invention provides an effective articulatedaquatic flipper of light-weight rigid construction which enhances theenjoyment of aquatic sports, such as swimming and skin diving. Theinvention has particular utility in skin diving uses, since the wearermust necessarily make a return stroke with the hand and flippercompletely submerged.

It will also be observed that the arrangement and construction of thesupport plate 11 in conjunction with the handle 20 and the wrist band 25precludes the transmission of high stress forces to the wrist of thewearer in that they are directly transmitted to the rigid portion of theforearm by reason of the arcuately curved lower surface afforded by therearward portion 15. Accordingly, the invention provides a device whichis safe to use, permits eflicient utilization of the wearers energy, andis readily releasably attached to the wearers arm and hand.

Although the invention has been herein shown and described in what isconceived to be the most practical and preferred embodiment, it isrecognized that departures may be made therefrom within the scope of theinvention, which is not to be limited to the details disclosed hereinbut is to be accorded the full scope of the claims so as to embrace anyand all equivalent devices and apparatus.

Having described my invention, what I claim as new and desire to secureby Letters Patent is:

1. An articulated aquatic flipper adapted for use as an aid inpropelling a person in a body of water comprising an elongated,longitudinally rigid support plate providing a substantially plane lowersurface adapted to contact the hand of a wearer and a transverselyarcuately curved surface partially to embrace the wrist and forearm ofthe wearer; a plurality of jointed rib members, each having at least twoelongated sections pivotally interconnected for relative movement abouta respective transverse axis, each of the members providing a forwardlyprojecting distal end and a rearward proximal end; reinforcing means inthe form of an upstanding elongated channel element having across-sectional configuration of an inverted U and being integrallycarried by each of the members to afford longitudinal rigidity thereto;means connecting each of said rib members to the support plate forpivotal movement about respective transverse axes to and from anextended swimming position and a retracted return-stroke position; aplurality of stop pins carried by the plate to limit the range ofmovement of said rib members to said extended swimming position; a stoppin carried by each of the rib members adjacent to said pivotalinterconnection of the sections to limit the range of pivotal movementto an extended position; a web of flexible, substantially impervious,stretch-resistant, waterproof material extended between said rib membersto provide a reaction surface when in an extended swimming position; andmeans secured to the support plate and adapted for releasably attachingthe plate to the arm of a wearer.

2. An articulated aquatic flipper adapted for use as an aid inpropelling a person in a body of water comprising an elongated supportplate providing a substantially plane lower surface adapted to contactthe hand of a wearer and a transversely arcuately curved surfacepartially to embrace the wrist and forearm of the wearer; a plurality ofelongated reinforcing ribs longitudinally extended and transverselyspaced on said plate member to enhance the longitudinal rigiditythereof; a plurality of jointed rib members, each having at least twoelongated sections pivotally interconnected for relative movement abouta respective transverse axis, each of the members providing a forwardlyprojecting distal end and a rearward proximal end; reinforcing meansintegral with and carried by each of the members to afford longitudinalrigidity thereto, said rib members having a cross-sectionalconfiguration of an inverted U and providing opposed, laterally extendedflanges aifording respective attachment surfaces; means connecting eachof said rib members to the support plate for pivotal movement aboutrespective transverse axes to and from an extended swimming position anda retracted return-stroke position, said connecting means providing apredetermined forwardly divergent relationship between said rib members;a plurality of stop pins carried by the plate to limit the range ofmovement of said rib members to said extended swimming position; a stoppin carried by each of the rib members adjacent to said pivotalinterconnection of the sections to limit the range of pivotal movementto an extended position; a web of flexible, substantially impervious,stretch-resistant, waterproof material extended between said rib membersand secured to the respective attachment surfaces thereof to provide areaction surface when in an extended swimming position; and meanssecured to the support plate and adapted for releasably attaching theplate to the arm of a wearer.

3. An articulated aquatic flipper adapted for use as an aid inpropelling a person in a body of Water comarena-7o prising an elongatedsupport plate providing a substantially plane lower surface adapted tocontact the hand of a wearer and a transversely arcuately curved surfacepartially to embrace the Wrist and forearm of the wearer; handle meansrigidly secured to and depending from said plate member and adapted formanual grasping by the wearer; a plurality of elongated reinforcing ribslongitudinally extended and transversely spaced on said plate member toenhance the longitudinal rigidity thereof; a plurality of jointed ribmembers, each having at least two elongated sections pivotallyinterconnected for relative movement about a respective transverse axis,each of the members providing a forwardly projecting distal end and arearward proximal end; reinforcing means integral with and carried byeach of the mem bers to afford longitudinal rigidity thereto, said ribmembers having a cross-sectional configuration of an inverted U andproviding opposed, laterally extended flanges affording respectivesubstantially flat attachment surfaces; means connecting each of saidrib members to the support plate for pivotal movement about respectivetransverse axes to and from an extended swimming position and aretracted return-stroke position, said connecting means providing apredetermined forwardly divergent relationship between said rib members;a plurality of stop pins carried by the plate to limit the range ofmovement of said rib members to said extended swimming position; a stoppin carried by each of the rib members adjacent to said pivotalinterconnection of the sections to limit the range of pivotal movementto an extended position; a web of flexible, substantially impervious,stretch-resistant, Waterproof material extended between said rib membersand secured to the respective attachment surfaces thereof to provide areaction surface when in an extended swimming position; and meanssecured to the support plate and adapted for releasably attaching theplate to the arm of a wearer.

References Cited in the tile of this patent UNITED STATES PATENTSFOREIGN PATENTS France Apr. 6, 1908 Germany Apr. 19, 1922

1. AN ARTICULATED AQUATIC FLIPPER ADAPTED FOR USE AS AN AID INPROPELLING A PERSON IN A BODY OF WATER COMPRISING AN ELONGATED,LONGITUDINALLY RIGID SUPPORT PLATE PROVIDING A SUBSTANTIALLY PLANE LOWERSURFACE ADAPTED TO CONTACT THE HAND OF A WEARER AND A TRANSVERSELYARCUATELY CURVED SURFACE PARTIALLY TO EMBRACE THE WRIST AND FOREARM OFTHE WEARER; A PLURALITY OF JOINTED RIB MEMBERS, EACH HAVING AT LEAST TWOELONGATED SECTIONS PIVOTALLY INTERCONNECTED FOR RELATIVE MOVEMENT ABOUTA RESPECTIVE TRANSVERSE AXIS, EACH OF THE MEMBERS PROVIDING A FORWARDLYPROJECTING DISTAL END AND A REARWARD PROXIMAL END; REINFORCING MEANS INTHE FORM OF AN UPSTANDING ELONGATED CHANNEL ELEMENT HAVING ACROSS-SECTIONAL CONFIGURATION OF AN INVERTED U AND BEING INTEGRALLYCARRIED BY EACH OF THE MEMBERS TO AFFORD LONGITUDINAL RIGIDITY THERETO;MEANS CONNECTING EACH OF SAID RIB MEMBERS TO THE SUPPORT PLATE FORPIVOTAL MOVEMENT ABOUT RESPECTIVE TRANSVERSE AXES TO AND FROM ANEXTENDED SWIMMING POSITION AND A RETRACTED RETURN-STROKE POSITION; APLURALITY OF STOP PINS CARRIED BY THE PLATE TO LIMIT THE RANGE OFMOVEMENT OF SAID RIB MEMBERS TO SAID EXTENDED SWIMMING POSITION; A STOPPIN CARRIED BY EACH OF THE RIB MEMBERS ADJACENT TO SAID PIVOTALINTERCONNECTION OF THE SECTIONS TO LIMIT THE RANGE OF PIVOTAL MOVEMENTTO AN EXTENDED POSITION; A WEB OF FLEXIBLE, SUBSTANTIALLY IMPERVIOUS,STRETCH-RESISTANT, WATERPROOF MATERIAL EXTENDED BETWEEN SAID RIB MEMBERSTO PROVIDE A REACTION SURFACE WHEN IN AN EXTENDED SWIMMING POSITION; ANDMEANS SECURED TO THE SUPPORT PLATE AND ADAPTED FOR RELEASABLY ATTACHINGTHE PLATE TO THE ARM OF A WEARER.